My wife filed Single on her W-2 taxes, instead of Married, Filing separately. What problems may arise from this once I file my taxes? Recently married before 2016.

Me and my wife recently got married before the beginning of 2016. Before getting married, she was claiming Single and 0 dependents on her W-4. She just recently filed her W2 under Single, instead of Married filing separately. What problems can arise whenever I go to file my taxes and input her Social in the info needed box, or what problems will arise at all?